DEFINED BENEFIT PLAN - Net periodic benefit costs (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Mar. 31, 2023	Mar. 31, 2022	Mar. 31, 2023	Mar. 31, 2022
Components of net periodic (benefit) expense:
Interest cost	$ 182	$ 79	$ 364	$ 137
Expected return on assets	(198)	(220)	(396)	(329)
Amortization of prior (gain) loss	(37)	116	(75)	277
Net periodic (benefit) expense	$ (53)	$ (25)	$ (107)	$ 85
Defined Benefit Plan, Net Periodic Benefit Cost (Credit) Excluding Service Cost, Statement of Income or Comprehensive Income [Extensible Enumeration]	General and Administrative Expense	General and Administrative Expense	General and Administrative Expense	General and Administrative Expense